The disclosed embodiments relate to knee replacements. More specifically, the disclosed embodiments relate to all-polyethylene, modular knee replacements and methods for utilizing and implanting the same.
Conventionally, a knee joint prosthesis includes a femoral implant and a tibial implant. The femoral implant and tibial implant are designed to be surgically implanted into the distal end of the femur and the proximal end of the tibia, respectively. The femoral implant is further designed to cooperate with the tibial implant in simulating the articulating motion of an anatomical knee joint.
These femoral and tibial implants, in combination with ligaments and muscles, attempt to duplicate natural knee motion as well as absorb and control forces generated during the range of flexion.
Typical knee replacements include trial components temporarily placed in the knee prior to implantation of the permanent components to help a physician to correctly fit the knee replacement to a particular patient. During the knee replacement procedure, the physician may assemble the trial knee joint prosthesis one or more times with different trial pieces of the knee replacement that are designed to be easily removable. When the correct size and orientation of the knee replacement is identified, then a corresponding size of a permanent knee replacement is permanently implanted, such as by cementing the permanent knee replacement into a resected portion of the bone, such as the tibia or femur.
However, even when this procedure is carefully followed, a physician may still find later during the procedure that the sizing is not quite correct. However, if the permanent piece is already in place, it is difficult to remove the incorrectly sized permanent piece without removing more of the bone and increasing the risk to the patient. Thus, there is a need for an all-polyethylene, permanent knee replacement that is still easily replaceable by a physician in the event that the trial fit is insufficient.